Edge-mounted, surface-mount package for semiconductor integrated circuit devices

Abstract

A flat package for semiconductor integrated circuit devices allows edge-mounting and surface-mount. The package may be molded plastic containing a semiconductor chip, and flat leads extend from one edge of the package. The leads are bent to provide an area to solder to conductors on a PC board. Mechanical positioning, mechanical support and spacing are provided by studs extending from the edge of the package adjacent the leads. The studs have stops formed at a position even with flat outer surfaces of the bent leads; the portion outward of the stops fits into holes in the PC board.

What is claimed is: 
     
       1. A surface mount integrated circuit structure, comprising: a printed circuit board having a surface for mounting integrated circuit devices, the surface having apertures for receiving nonconductive portions of the integrated circuit devices; and   a semiconductor integrated circuit device having a relatively flat nonconductive package encapsulating a semiconductor chip, a plurality of conductive leads extending from one edge of the package, and a plurality of nonconductive studs extending from the one edge of the package that are shaped to fit into the apertures of the printed circuit board for mechanically positioning and supporting the package when the conductive leads are soldered to the printed circuit board.   
     
     
       2. The structure of claim 1 wherein the conductive leads are bent to present a face generally perpendicular to the relatively flat package. 
     
     
       3. The structure of claim 1 wherein the nonconductive studs have a stop on them to limit the extension of the studs into the printed circuit board and provide a selected spacing between the edge of the package and the printed circuit board. 
     
     
       4. The structure of claim 3 wherein the conductive leads are bent to present a face generally perpendicular to the printed circuit board and aligned with said stop. 
     
     
       5. The structure of claim 2 wherein the nonconductive package is a plastic package. 
     
     
       6. The structure of claim 4 wherein the nonconductive package is a plastic package. 
     
     
       7. An integrated circuit surface mount structure, comprising: a printed circuit board having a surface for mounting integrated circuit devices, the surface having apertures for receiving nonconductive supporting parts of the integrated circuit devices; and   an integrated circuit device having an integrated circuit encapsulated by a nonconductive generally flat package, a plurality of conductive leads along one edge of the package extending into the package and connected to the integrated circuit, and a plurality of integral studs along the edge of the package shaped to fit into the apertures of the printed circuit board for mechanically positioning and supporting the package when the conductive leads are soldered to the printed circuit board.   
     
     
       8. The structure of claim 7 wherein the nonconductive generally flat package is a plastic package. 
     
     
       9. The structure of claim 8 wherein the the studs have spacers on them to limit the extension of the studs into the apertures and to provide a selected spacing between the edge of the package and the printed circuit board. 
     
     
       10. The structure of claim 9 wherein the conductive leads are shaped in alignment with the spacers so that the conductive leads relatively abut the surface of the printed circuit board when the studs of the package are inserted into the apertures of the printed circuit board. 
     
     
       11. A vertically oriented semiconductor package, designed for surface mounting on one of a pair of planar surfaces of a printed circuit board, said package comprising: a body having a pair of substantially parallel, vertical planar sides, lower and upper horizontal edges and a substantially vertical edge at each end of the package;   a semiconductor die having a face on which integrated circuitry is constructed, said die being encapsulated within said body such that said face is positioned between and substantially parallel to the vertical planar sides of said body;   a plurality of inline leads, each of which is electrically connected, within said body, to a portion of the circuitry on said die, and each of which extends in a downward direction through the lower edge of said body, below which it is bent such that it is disposed against the planar surface of the circuit board when the package is in a mounted position thereupon;   at least one downward-facing anchoring pin integral with said body at each end thereof; and   means for securely attaching each anchoring pin to the circuit board in order to maintain a mounted position thereupon during solder reflow operations.   
     
     
       12. The semiconductor package of claim 11, wherein said means for securely attaching comprises a nub on the end of each anchoring pin which is secured within a recess in said circuit board. 
     
     
       13. The semiconductor package of claim 12, wherein each of said anchoring pins has a shoulder that is larger than the diameter of the recesses in said circuit board which seats against said one planar surface of said circuit board. 
     
     
       14. The semiconductor package of claim 11, wherein said means for securely attaching comprises an extension on the end of each anchoring pin which, when said anchoring pins are inserted from said one surface through holes in said circuit board that are properly aligned and properly sized for a forced insertion fit, said extensions are frictionally locked in said holes. 
     
     
       15. The semiconductor package of claim 14, wherein each of said anchoring pins has a shoulder that is larger than the diameter of its corresponding hole in said circuit board, said shoulder seating against said one planar surface of said circuit board. 
     
     
       16. A semiconductor integrated circuit device package assembly comprising: a printed circuit board having a planar major surface with electrically conductive areas thereon;   a body having a pair of substantially parallel, vertical planar sides, lower and upper horizontal edges and a substantially vertical edge at each end thereof;   a semiconductor substrate having a face on which integrated circuitry is constructed;   said semiconductor substrate being encapsulated within said body such that said face of said semiconductor substrate is positioned between and substantially parallel to the vertical planar sides of said body and defining therewith a semiconductor device package;   a plurality of conductive leads extending from at least one horizontal edge of said body, at least some of said plurality of conductive leads being electrically connected within said body to a portion of the integrated circuitry on said semiconductor substrate;   each of said plurality of conductive leads respectively including an outer contact portion engaging an electrically conductive area on said planar surface of the circuit board when the semiconductor device package is in a vertically mounted position thereupon;   at least one anchoring member mounted on said body and extending from said at least one horizontal edge of said body; and   means for securely attaching each anchoring member to the circuit board in order to maintain a vertically mounted position of said semiconductor device package thereupon during solder reflow operations.   
     
     
       17. A semiconductor integrated circuit device package assembly as set forth in claim 16, wherein the outer contact portion of each of said plurality of conductive leads is angularly disposed with respect to the remainder of the corresponding conductive lead. 
     
     
       18. A semiconductor integrated circuit device package assembly as set forth in claim 16, wherein said body is made of molded plastic, and said at least one anchoring member is of molded plastic integral with said body.   
     
     
       19. A semiconductor integrated circuit device package assembly as set forth in claim 18, wherein said at least one anchoring member comprises an anchoring pin integral with said body at each end thereof; and said means for securely attaching comprises a nub on the end of each anchoring pin and of reduced size with respect to the remainder of the anchoring pin which nub is secured within a recess in said circuit board.   
     
     
       20. A semiconductor integrated circuit device package assembly as set forth in claim 19, wherein each of said anchoring pins has a shoulder defined thereon between the nub of reduced size and the remainder of the anchoring pin, the shoulder on each anchoring pin being larger than the diameter of the respective recesses in said circuit board and seating against said planar surface of said circuit board.